Myriam Marianne Chaumeil1, Gerd Melkus1, Sarah Woods1, Robert M. Danforth1, Alessia Lodi1, Aaron Robinson2, Joanna J. Philips2, 3, Sabrina M. Ronen1
1Radiology, University of California, San Francisco, San Francisco, CA, United States; 2Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States; 3Pathology, University of California, San Francisco, San Francisco, CA, United States Localized 1H MRS and hyperpolarized (HP) 13C MRSI were performed in vivo at 14.1Tesla to assess total and HP lactate levels, respectively, in two orthotopic models of glioblastomas with significantly different intracellular lactate levels: U87IDHmut[Lac]>U87IDHwt[Lac]. In line with the intracellular levels, in vivo 1H lactate levels were significantly higher in U87IDHmut. In contrast, HP lactate-to-noise and lactate-to-pyruvate ratios from the same tumor voxel were not significantly different between the cell lines. This discrepancy confirms that HP 13C MRSI and 1H MRS provide complementary information, the 1H-detected lactate level not being a dominant factor in the detected HP lactate production.